An electron-donating system composed of a CIDS@CFO@F0C0 catalyst for the sustainable generation of free radicals to inactivate pathogens

Abstract

Transition-metal-catalyzed reactive oxygen species (ROS) play an important role in existing bactericidal systems, but there are some problems, such as poor stability, ease of dissolution, and difficulty in reusing. To address the issue of stability, we have developed a sufficient electron-donating (SED) system. In the presence of the two most active transition metals with multiple valences, several as-formed redox pairs can provide sufficient electrons, and then effectively trigger the reduction of H₂O/O₂ to produce ¹O₂, ·OH and ·O₂⁻ without any assistance from extra energy or other active oxidants. Consequently, the SED system showed 100% removal efficiency for Escherichia coli in 2 h, and also showed remarkable stability and reusability with 85% inactivation after 11 repetitions. It is worth noting that ·OH and ¹O₂ play a major role in the bactericidal process. While ·O₂⁻ mainly plays a role in promoting the formation of ¹O₂ and ·OH.